Traditional incandescent lighting devices are currently being replaced by more energy efficient alternatives, such as halogen lighting devices and light emitting diode, LED, lighting devices. When designing new lighting devices, it is desirable to resemble the traditional design of incandescent lighting devices in order to enable use of existing manufacturing equipment.
In traditional incandescent light bulbs, a tungsten filament is normally supported in a glass envelope by means of a glass stem. An LED bulb comprising a substrate, an LED, and an LED driving plate welded above the substrate is shown in CN 203115641 U. The driving plate is connected with a steel needle in the middle of the core column through a chuck, which may provide inadequate fixation of the driving plate to the core column. The air flow of the LED bulb shown in CN 203115641 U will be blocked since the driving plate is mounted directly to the substrate. Further, the driver components are mounted within the LED bulb and will outgas and may consume oxygen which reduces the light output from the LEDs.
In US2013/0271989 a lamp is disclosed with an LED array disposed in an optically transmissive enclosure. A gas, e.g. oxygen or helium, is contained in said enclosure for transporting the heat from the LEDs to the enclosure. The LED array is supported by a stem-like structure.
Further, US2014/0036497 describes a retrofit type of lamp with a LED module and a heat sink and a reflector which is thermally coupled to the heat sink such that the heat is at least partially dissipated to the ambient through the reflector.